609 Wear Resistant High-Temperature (425°C) Metal Bellows Seal with Narrow Cross-Section Design for Industrial Pumps
609 Metal Bellows Seal
Feature:
The Type 609 is a high-temperature (to 425°C/800°F) rotating seal head assembly that incorporates all of the rugged features of the Type 604, but is intended for those demanding applications where a dependable, high-strength, rotating seal is preferred. A narrow cross-section design enables the Type 609 to fit in the most popular pumps without expensive and time-consuming seal chamber modifications. This makes it the ideal seal for heat transfer, hydrocarbon and other applications that commonly use pumps with limited seal chamber clearances. Typical applications include hot hydrocarbons, aqueous solutions, aromatic fractionation products, crude oil fractionation products and heat transfer fluids.
Replacement to:
Replacing the mechanical seal of John Crane 609
Operational Conditions:
1. Temperature: -20ºC to +180ºC
Pressure: ≤2.5MPa
Speed: ≤15m/s
2. Materials:
Stationary Ring: Ceramic, Silicon Carbide, TC
Rotary Ring: Carbon, Silicon Carbide
Secondary Seal: NBR, EPDM, , PTFE
Spring and Metal Parts: Steel
3. Seat Type:
4. Applications: Clean water, sewage water, oil and other moderately corrosive fluids
Advantage
- wear resistant
- superior sealing effects
- low friction
- easy replacement
- customized mold
- quality management system
- exquisite packaging
- wide application
- drawing will be provided for free with mass production
Why Choose Us
Question one: Are you a factory or a trade company?
Answer: We are a factory and have our top sales for the trade service. Our factory’s address is No28-1 Shuangchuang Park, Chengxi Road, Jiashan County, Jiaxing, Zhejiang, China
Question two: How do I believe your quality?
Answer: The products are made of Superior Raw Materials,The production of all our products is strictly controlled by the professional quality control department. And our boss will arrange the random inspections for each order. Sure the third party inspection is available.
Question three: Can I try to get a sample before the order.
Answer :Yes. Sure, you can ask the sales for the samples request. We can provide free piece of o-rings, springs and so on.

1. Core Structure and Design Features
| Feature | Detailed Description |
|---|---|
| Rotary Bellows Design | Narrow radial cross-section, compatible with most standard pumps without the need for costly seal chamber modifications |
| Edge-welded Bellows | Made of Alloy 718 (standard) or heat-treated AM350 stainless steel (optional), optimized with a 45° inclination angle to reduce stress |
| Elastomer-free Design | Uses flexible graphite static seals to avoid elastomer failure at high temperatures |
| Balanced Structure | Optimized load coefficient reduces seal face pressure and extends service life |
| Dual-layer Diaphragm Option | Suitable for high-pressure applications to enhance pressure resistance |
| API-682 Certification | Complies with international sealing standards to ensure reliability in industrial applications |
| Multi-end Face Configuration | Offers single-end and double-end cartridge seal arrangements, with optional auxiliary seal systems |
2. Technical Performance Parameters
| Parameter Category | Value Range |
|---|---|
| Temperature Range | -75°C to 425°C (-100°F to 800°F) with flexible graphite static seals |
| Pressure Range | Standard type: Vacuum to 25 bar(g) (360 psi(g)) |
| Speed Limit | 25 m/s (5000 fpm) |
| Shaft Diameter Range | 18-175 mm (0.75-7.0 in) |
| Seal Face Material | Premium carbon graphite, silicon carbide or tungsten carbide, selectable according to medium characteristics |
| Metal Component Material | 304 stainless steel, 316 stainless steel, Hastelloy C, Alloy 718, etc., suitable for different corrosive environments |
3. Main Application Fields
- Petrochemical and Refining Industry: High-temperature hydrocarbons, aromatic fractionation products, crude oil fractionation systems, heat transfer fluids
- Chemical Industry: Corrosive chemicals, organic acids (e.g., naphthenic acid), sulfur compounds, aqueous solutions and lubricants
- Power Industry: Hot oil pumps, heat transfer oil pumps, boiler feed pumps
- Other Rotating Equipment: Compressors, screw pumps, oil extraction equipment and other industrial machinery requiring strict sealing
5. Summary of Key Advantages
- Strong High-temperature Adaptability: Resistant to temperatures up to 425°C, far exceeding ordinary mechanical seals
- Wide Pressure Range: Maximum pressure of 25 bar for single-layer diaphragm and 69 bar for dual-layer diaphragm
- Excellent Corrosion Resistance: Multiple alloy materials available, especially suitable for harsh working conditions containing sulfur and organic acids
- Easy Installation: Narrow cross-section design enables installation on most standard pumps without modifying the seal chamber
- Long Service Life Design: The combination of balanced structure, edge-welded bellows and high-quality seal face materials reduces wear
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.